While Iranian officials insist the explosion at the Bid Ganeh base was accidental, caused by the movement of ammunition, claims from anonymous western and Israeli officials that Saturday's blast was a covert Israeli operation have gained momentum.

Leading Israeli daily Yediot Ahronot picked up a post by US blogger Richard Silverstein claiming the Mossad had teamed up with Iranian militant group Mujahideen e-Khalq (MEK) to execute the alleged attack. MEK denies involvement in the attack.

Leftwing broadsheet Ha'aretz also led with reports that a western intelligence source quoted in Time magazine had claimed the Mossad carried out the attack in an attempt to stall Iran's development of a nuclear weapon. The official is said to have warned: "There are more bullets in the magazine."

The blast at the base, which is reported to have been a storage facility for long-range missiles, was so powerful that it was said to have been felt 30 miles away in the capital, Tehran.

Among those killed was Major General Hassan Moghaddam, the Revolutionary Guard Commander charged with "ensuring self-sufficiency" in armaments, and described by Iranian media as a pioneer in Iranian missile development.

Israel's defence minister, Ehud Barak, responded to news of Moghaddam's death by saying: "May there be more like it."

Prime minister Binyamin Netanyahu's office refused to comment on growing speculation of the Mossad's involvement. Ilan Mizrahi, former head of the national security council and former deputy head of the Mossad, also would not be drawn into substantiating the claims: "I have no idea whether this blast was accidental or whether it was sabotage. But I will say God bless those who were behind it, because the free world should be doing its best to prevent Iran from achieving nuclear military capability."

Both the US and France have offered close co-operation with Israel, threatening increased sanctions unless Iran responds with transparency to the nuclear watchdog report. Earlier this month, the Knesset debated the bombing of Iran to prevent further nuclear development, with Netanyahu and Barak said to supporting military strikes.

"There is nothing in this latest IAEA report that Israel hasn't known for a long time. Their arsenal of long-range missiles is also too often overlooked. I believe a military strike is an option that should be put clearly on the table," Mizrahi said. "Something should be done to stop Iran. I think in the end [Israel] will stand alone."

Iran's envoy to the IAEA says any nuclear development is for peaceful means and that the material evidence against has been fabricated by the US.

Israel has been linked to several previous incidents in Iran similar to Saturday's explosion, including an explosion at a Shahab facility in south-western Iran in 2010 and a bomb attack earlier that year in Tehran, in which Iranian physicist Masoud Ali Mohammadi was killed.